The present invention relates to a socket adapter for coupling a socket to a ratchet socket wrench, and more particularly to a quick-release socket adapter which enables the loaded socket to be quickly released.
A variety of ratchet socket wrenches have been disclosed for grasping and turning bolts, nuts, etc., and have appeared on the market. FIG. 1 shows a conventional ratchet socket wrench for this purpose. When in use, the socket is coupled to the polygonal driving shaft of the ratchet socket wrench and secured thereto by a steel on in a radial hole on the polygonal driving shaft. When not in use, the socket is directly removed from the polygonal driving shaft of the ratchet socket wrench by force. FIG. 2 shows another structure of conventional ratchet socket wrench. This structure of ratchet socket wrench has a release button controlled to release the steel ball from the socket being coupled to the polygonal driving shaft of the ratchet socket wrench. FIGS. 3 and 4 show two socket adapters used for coupling a socket to a ratchet socket wrench. These two socket adapters commonly have a polygonal front end for holding a socket, and a steel ball moved in and out of a radial hole on the polygonal front end to lock the socket mounted on the polygonal front end. When not in use, the user must employ such effort to remove the loaded socket from the polygonal front end of the adapter. FIGS. 5, 6 and 7 show a socket adapter which enables the user to dismount the loaded socket with less effort. This structure of socket adapter comprises a longitudinal hole, a radial hole perpendicularly extended from the longitudinal hole to the periphery of the polygonal front end thereof, a rear coupling end for coupling to a ratchet socket wrench, a steel ball moved in and out of the radial hole for locking socket being mounted on the polygonal front end, a transverse hole intersecting the longitudinal hole, a stop rod inserted into the longitudinal hole, the stop rod having hooked portion at one end and a sliding way adjacent to the hooked portion, a spring mounted inside the longitudinal hole and stopped against one end of the stop rod, and a release control rod inserted into the transverse hole, the release control rod having a retaining portion for engagement with the hooked portion of the stop rod. The spring imparts a forward pressure to the stop rod, causing the hooked portion of the stop rod to be engaged with the retaining portion of the release control rod. When engaged, the steel ball is partially forced out of the radial hole to lock the loaded socket. When the release control rod is depressed, the stop rod is forced backwards to compress the spring, and to release the steel ball from the loaded socket, enabling the loaded socket to be removed from the polygonal front end of the adapter. This structure of socket adapter still has drawbacks. Because the location of the release control rod is near the polygonal front end and far away from the rear coupling end of the adapter, the user just holds the ratchet socket wrench with one hand and operate the release control rod with the other hand when unlocking the loaded socket. Another drawback of this structure of socket adapter is its complicated structure. Because the procedure of processing the retaining portion on the release control rod and the hooked portion and sliding way on the stop rod is complicated, the manufacturing cost of this structure of socket adapter is high.
It is one object of the present invention to provide a quick-release socket adapter for coupling a socket to a ratchet socket wrench which enables the loaded socket to be quickly released from the socket adapter. It is another object of the present invention to provide a quick-release socket adapter which can be conveniently operated with one hand to release the loaded socket. It is still another object of the present invention to provide a quick-release socket adapter which is inexpensive to manufacture. To achieve these and other objects of the present invention, there is provided a socket adapter comprised of a hollow elongated casing, the casing having a cylindrical base, a polygonal front end at one end of the cylindrical base for holding a socket, and a coupling portion at an opposite end of the cylindrical base for coupling to a ratchet socket wrench, a spring, a stop rod inserted into the casing and forced by the spring to push a steel ball partially out of a radial locating hole on the polygonal coupling rod of the casing to lock the socket being mounted on the polygonal coupling rod of the casing, and a release control rod inserted through a transverse through hole on the ratchet socket wrench coupling portion of the casing and moved to lock/unlock the stop rod, the release control rod having a flank curved outwards on the middle, the flank being engaged with a recessed top wall of a head at one end of the stop rod when the release control rod is moved to a first position in the transverse through hole on the ratchet socket wrench coupling portion of the casing, enabling the steel ball to be forced out of the radial locating into engagement with the socket mounted on the polygonal coupling rod of the casing, the stop rod being forced forwards by the flank when the release control rod is moved to a second position in the transverse through hole on the ratchet socket wrench coupling portion, thereby causing the steel ball to fall in the radial locating hole away from the socket mounted on the polygonal coupling rod.